Microtomographic evaluation of the bone-cell interactions with a silorane-based composite

The low-shrink Silorane-based composite could bond effectively to bone and showed the potential be used as a bone cement. Bone organ culture maintains the anatomical order, natural cell-to-cell and cell-to-matrix relationship. The purpose of this study was to evaluate the responses of bone cells to a Silorane-based composite which was compared with a representative polymethyl methacrylate (PMMA) bone cement. The critical size defects were created through the parietal bones from one litter of mice. The paired bones were divided into two groups: Silorane-based composite group and PMMA group. The prepared two groups of disks were put into the defects. The cultures were grown in vitro for 38 days and analyzed with microcomputed-tomography, dissecting-microscope, phase- contrast-microscope, scanning-electron-microscopy, and energy- dispersive-X-ray. At the 10th day, the Silorane disk was almost fully covered by a sheet of cells but the cells hardly attached to the disk surface. The edge of the PMMA disk was covered by a sheet of cells and the migrated individual cells attached to the whole surface of the disk. At the 38th day, some cells attached to the exposed disk area of the Silorane disk while the formed tissues covered the whole surface of the PMMA disk. The collagen fibers, globular deposits and bone formation were visible in both groups. The Silorane-based composite showed promise as a potential bone cement when compared with PMMA which is used in clinical orthopedics. However, the cell attachment to PMMA was evidently better than to Silorane-based composite.